I thinks it C, this a difficult question but idk, that my closest guess...
Oliver is incorrect because if he were correct he would learn for 2 hours and 15 minutes because, 45 minutes * 3= 2:15 minutes.
Answer:
x = -3
y = -8
Step-by-step explanation:
2y = x - 13
3x = y - 1; let y = 3x + 1
substitute to solve for 'x':
2(3x + 1) = x - 13
6x + 2 = x - 13
5x + 2 = -13
5x = -15
x = -3
solve for 'y':
3(-3) = y - 1
-9 = y - 1
-8 = y
2 gallons were left at the end of the day
THE SLOPE IS -2
if we have the coordinates of two points on a line, we can find the slope with this formula:

so the slope is

the answer is -2
good luck